Method of producing visual depth in projected pictures



July 1o, 1923; 31,461,332

l T. H. MARTI-:N

METHOD OF PRDUCING VISUAL DEPTH IN PRJECTED PICTURES Filed April 5; 1922 Pictu-res, described in' the following specifi-f A Patented `luly lO, 1923.

Latium? UNITED STATES raraur orties THOMAS HENRY MARTEN, 0F TORONTO, ONTARIO, CANADA.

METHOD OF PRODUCING VISUAL DEPTH IN PROJECTED PICTURES.

Application filed April 3, 1922. Serial N'O. 549,005'.

To all 'whom t may concern Be it known that I, THOMAS HENRY MAR- TEN, a subject of the King of Great Britain, and resident of the city of Toronto, county of York, Province of Ontario, in the Dominion of Canada, have invented certain new and useful Improvements in4 aMethod. of .Producing Visual Depthin Projected vfocal adjustment in the eye ofthe observer to automatically adjust itselfv to the vary-..

ing conditions of depth or distancerepre-v 'sentedthe combined pictures, such result being accomplishedby utilizing the ten-v dencyofthe eye to automatically adjust itT self to 4changes in the visual angle of obs jects within the vision field.

' It isve well knownl to those conversant with the plcture producing art that the eye of the f observer, after a brief period ofv .first viewing. a picture, becomes accustomed kto' the '-factthat the visual observatiorris confined't'c a fiat surface.

Thefeye in its normal function' and under ordinary' conditions is constantly changing.

focus' andif .conditions surrounding a pic-v ture-are such as to maintain this normal' activity-,then the eye will function normally .and reajd into the picture the third dimension ofjdepth. l

This is quite noticeable in that when first entering.' a theatre where a picture is being shown, it distinctly, shows'the element of depth but afterA it has been viewed .for a short time theeye assumes a xed 4focus and the picture assumes a iiat; appearance which is unnatural and'causesjeyel strain. Thefprinciple'pf -the'third dimension in vision 1s partlybased on the fact' that we have two eyes and-'the mental4 reaction with the optic nerves issuch' as tojudge distance by reason of vbinocular convergence but -such convergence is not the only element or made injthe following terms:

componentv of general vision which produces the visual physical sensation of the third dimension and in order that a thorough understanding of the present invention be had a statement of visual conditions may be First: the psychological reactionto the physiological action of the function of convergence by'binocular cooperation to locate the position of the object;

Second: the' psychological reaction to the physlological.actionof the function of focal adjustment of the optic lens to "produce a sharp retinal image of the object wherever located.

Third: the purely psychological element ofthe association of real objects with each other as they are known to be through experience with them in ourthree dimensional world.

Ordinarily the observer is consciously or sub-eonsciously experiencing the physical A.sensation 5f the change of the angle of c on- 'vergence and the same is true of the change.

' ofthe focus of the optic lens. The observer' is accustomed to cw sciouslypor' sub-consciously experience the directV association between the function of convergence and the functionof focal adjustment and upon the ldistance of the observer from 4the object looked at will depend the ma ni'tude of tlie angle of convergence and the degree of focal adjustment, both'becoming less as the distance is increased but both maintainin true association each with the' other whic is a normal sensation. v

When a picture 1s projected on to a plane VLsurface at a distance close enough to lform a conscious angle of convergence the eye adjusts itself to this condition and the'sensation produced is that both the angle of convergence-.and the focal adjustment are held .fixed in thatno one part of the plane surface requires a change of convergence or focal adjustment as compared with any other part and when ,the eyes, which nature has vfurnished as measuring instruments, form a fixed angle ofl convergence combmed with a fixed focus they read only in two dimensions, namely, height and breadth. This suspends the normal activity of the muscular system'controlling the optic meehanlsm of the observer, that is to say, the normal iexing and reiexing of the muscles of the `eyes are suspended and the abnormal condition produced is what produces eye strain. In the ordinary conditions of vision the senses may be specifically focused u on an object a certain distance from t e eye but there are other elements which are affecting such senses sub-consciously in the form of other objects nearer or farther away.

It is4 of course well established Vthat We judge distance by the visual size of the object and while this is carried into effect in screened pictures and we observe and properly interpret 'that an object is in the immediate foreground or far away, yet there is a'known fixed distance between the observer and the picture and this produces the condition of fixed focus in the eyes of the observer as above set forth and results in the effect of a flat and unnatural picture.

This invention proposes to introduce an element outside of the actual central picture depicted which will maintain normal focal activity. n

It is well known that as objects approach the observer their visual dimensions and brightness or visibility increase and comparative location is judged by these conditions. If'therefore an element is introduced in the visual angle which simulates a change in distance the eye will react to the suggestion and be relieved of the fixed focal and resultant straining effect of the central picture.

The invention-is diagrammatically illustrated in the drawings, Figure 1 being the dia ram of a dat screen.

igure 2 is a diagram illustrating an image projected on the screen and suroundingrthe central picture.

igure 3 is an elevational diagram of the image shown in relation Vto the eye of the observer.

Figure 4 is a view similar to Figure 3 illustrating the illusion created by a change in the image.

The area A represents the main or central icture which is surrounded by the area and Aupon this marginal area is projected the imageC of an object or objects which will form a suitable setting for the picture, such as an architectural structure, or a frame, which may be supplemented by hangings as shown.

The image C is of course luminous and at a certain intensity of luminosity, say medium, it assumes a certain location in the mind of the observer on account of the natural judgment through the visual angle it embraces as illustrated in Figure 3. lf this image C is caused to vary in size, that is, it is made to gradually creep inward toward the central picture, or expand away vfrom it and coincidently its luminous intensity is diminished or increased it will have a direct effect upon the visual angle as illustrated in Figure 4.Y

If A is the central picture and the luminous image C has the dimension described by the boundary of A in Figure 3, the visual angle S is assumed, but if the image is distended to C and coincidently its dimension c is proportionately increased the visual angle changes to S and the observer F in accord with the known laws of vision will interpret that the image C has been advanced toward him as indicated by the line X, Figure 4. This illusion will of course be accentuated if the luminous intensity is coincidently increased.

The eect of this illusion is to interpose an element which will partially distract the nerves of the eye in the manner that the eye nerves are accustomed to function andas the framing image appears to move forward or backward there are produced two principal -visual angles, one encompassino' the central picture and one encompassing the surrounding luminous area. The eye in attempting to follow both angles which operate at variance with each other, fails to definitely locate the focal depth location of the central icture and this flexible focal condition proguces the interpretation of depth in the central picture and relieves eye strain.'

What I claim as my invention is 1. A method of producing visual depth in projected pictures, consisting in locating about the picture a fiexible image forming a visual attraction and maintaining focal activity in the eye ofthe observer.

2. A method of producing visual depth in projected pictures, consisting in locating about the picture a luminous area of increasing and decreasing dimensions producing variation in the visual angle.

3. A method of producing visual depth in projected pictures, consisting in locating about the picture an image of variable lu- V minosity,

4. A method of producing visual depth in projected pictures, consisting in locating about the picture a flexible image of variable luminosity.

5. A method of producing visual depth in projected pictures, consisting in surrounding the main picture with an image which' is maintained in constant movement expand ing or contracting to induce focal activity in the eye of the observer.

THUMAS HENRY MARTlllii. 

